Rails precision error

Posted by dontangg on Stack Overflow See other posts from Stack Overflow or by dontangg
Published on 2011-01-04T07:26:18Z Indexed on 2011/01/04 7:53 UTC
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precision

When I run this in my Rails application:

my_envelope.transactions.sum(:amount)

This SQL is shown in the log files:

SQL (0.3ms)  SELECT SUM("transactions"."amount") AS sum_id FROM "transactions" WHERE (envelope_id = 834498537)

And this value is returned:

<BigDecimal:1011be570,'0.2515999999 9999997E2',27(27)>

As you can see, the value is 25.159999. It should be 25.16. When I run the same SQL on the database myself, the correct value is returned.

I'm a little confused because I know that there are precision problems with Floats, but it is returning a BigDecimal. The SQL column type is decimal. Any ideas?

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